Effects of Rhomboid Intercostal Block on Postoperative Pain Management and Chronic Pain Incidence in Mastectomies

Koç University

Status: Completed

Conditions: Mastectomy; Chronic Pain Following Surgical Procedure for Cancer; Rhomboid Intercostal Block

Treatments: Procedure: Rhomboid Intercostal Nerve Block

Study type: Interventional

Funder types: Other

Identifiers

NCT06756048

2023.391.IRB1.138

Details and patient eligibility

About

The goal of this clinical trial is to evaluate the effects of the Rhomboid Intercostal Block (RIB) on postoperative chronic pain prevalence at 3 months (primary outcome) and on acute pain control, total opioid consumption, and the incidence of opioid-related side effects within the first 24 hours (secondary outcomes) in patients undergoing elective mastectomy surgery.

The main questions it aims to answer are:

Does the application of RIB reduce the prevalence of chronic pain at 3 months postoperatively? Does RIB improve acute pain control and reduce opioid consumption and related side effects in the first 24 hours postoperatively? Researchers will compare patients who receive RIB under general anesthesia to those who do not receive the block to determine its effectiveness in reducing chronic pain prevalence, acute pain scores, and opioid-related outcomes.

Full description

Primary Outcome Measures

The primary outcome is the prevalence of chronic pain at 3 months in patients undergoing mastectomy surgery. For patients reporting pain, additional parameters will be assessed, including:

Pain characteristics: location, frequency, intensity, and radiation. Factors that exacerbate or alleviate pain. Impact of pain on quality of life (measured on a 1-5 scale). Types and quantities of analgesics used. Secondary Outcome Measures

Acute Pain Scores:

Pain levels at 1, 6, 12, and 24 hours postoperatively at rest, measured using the Numeric Rating Scale (NRS).

Opioid Consumption and Side Effects:

Total opioid consumption (morphine and tramadol) within the first 24 hours postoperatively.

Incidence of opioid-related side effects, such as nausea, vomiting, and pruritus.

Patient Satisfaction and Sleep Quality:

Satisfaction with the analgesic method (e.g., very satisfied, satisfied, neutral, dissatisfied, very dissatisfied).

Sleep quality ratings (very good, good, moderate, poor, very poor). Willingness to use the same analgesic method again (yes/no).

Chronic Pain Impact on Daily Life (for patients with pain at 3 months):

Degree of limitation in physical activities, household/work tasks, and social life (scored on a scale from 0 = no limitation to 5 = constant limitation).

Impact on psychological well-being (scored on a scale from 0 = no impact to 5 = constant impact).

Study Design and Participants This prospective, randomized, controlled study will be conducted at Koç University Hospital. Participants will include 90 patients undergoing elective mastectomy surgery, aged 18-80 years, and classified as ASA I-III according to the American Society of Anesthesiologists. Written informed consent will be obtained from all participants.

The sample size calculation was based on a 2020 meta-analysis reporting a 59% prevalence of chronic pain at 3 months in patients without any regional block. Using select-statistics.co.uk software, with a two-proportion sample test, a 50% reduction in chronic pain prevalence was considered significant. With a p-value of 0.05 and 80% power, 43 patients per group were required. To increase robustness and account for potential dropouts, 45 patients per group (90 total) will be enrolled.

Randomization and Blinding: Participants will be randomized into two groups using randomizer.org software. RIB will be performed before induction of general anesthesia. No blinding will be performed due to the nature of the intervention.

Enrollment: 90 patients

Sex: Female

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients undergoing one of the following procedures: benign mass excisions, modified radical mastectomies (MRM), simple total mastectomies, nipple-sparing mastectomies, or skin-sparing mastectomies, regardless of additional procedures such as sentinel lymph node biopsy (SLNB), axillary lymph node dissection (ALND), or implant placement.

Exclusion criteria

• Patients undergoing breast augmentation, reduction, or mammoplasty without a mass.
• Patients with a BMI > 35.
• Emergency cases.
• Patients with bleeding diathesis.
• Known allergy to medications used in the study.
• Patients with asthma.
• Patients diagnosed with chronic kidney failure.
• Pregnant or lactating patients.
• Patients with chronic opioid use.
• Patients with cooperation issues or inadequate communication ability.
• Male patients.

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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90 participants in 2 patient groups

Allocated to Intervention (Rhomboid Intercostal Block)

Experimental group

Description:

Group I: RIB In the first group (Group RIB), patients will receive a Rhomboid Intercostal Block immediately before the induction of general anesthesia. The procedure will be performed with the patient sitting upright and premedicated with anxiolytics. Using ultrasound guidance, a 50 mm block needle will be inserted into the auscultatory triangle (interfascial plane located lateral to the erector spinae muscle, beneath the rhomboid major, and over the intercostal nerves). A total of 20 ml of 0.25% bupivacaine will be administered at this site. If the surgery is unilateral, the RIB will be applied only on the surgical side. For bilateral surgeries, 20 ml of bupivacaine will be administered to each side.

Treatment:

Procedure: Rhomboid Intercostal Nerve Block

Allocated to No Intervention (Control Group)

No Intervention group

Description:

Group II: Control Group In the second group (Control Group), patients will undergo the surgical procedure without receiving a Rhomboid Intercostal Block (RIB) or any other regional anesthesia technique. Standard general anesthesia protocols will be followed for these patients, and postoperative pain management will be conducted using systemic analgesics according to the institution's routine practice.